Driving mechanism for clinker grinders



Dec. 6, 1927. 1,651,433

D. K. BEACH DRIVING MECHANISI FOR CLINKER GRINDERS Filed June 12, 1922 2 Sheets-Sheet l filed-i+fgca5w A TTORNEY.

Dec. e, 1927. 1,651,433

D. K. BEACH DRIVING MECHANISM FOR CLINKER GRINDERS Filed June 12, 1922 2 Sheets-Sheet 2 Z0' INVENTOR. DHV/D K. Banc/1 ATT /RNEYO`- manna Dee. 6,1921. p UNITED STATES PATENT OFFICE.

DAVID I. BEACH, 'Ol' WORCESTER, ISSACHUSETTS, ASSIGNOR T0 RILEY STOIER COB- PORATION, A CORPORATION l' MASSACHUSETTS.

DRIVING I ECHANISM EOE CLINKEB, GBINDEBS.

Application-tiled .Tune 12, 19,28. Serial No. 587,881.

In the operation of furnaces e uipped with mechanical stokers, it is desira le to automatically limit the movement of the clinker grinder with which such stokers are commonly equipped. Automatic devices for this purpose not only conserve the operators time, but prevent damage caused by too extensive operation of the clinker grinder, which may otherwise wholly uncover and expose the roll to the heat of the furnace.

It is the object of -my invention to provide mechanism, preferably electrical, by which the operation of the grinding roll in either direction may be automatically lim- 1s ited.

My invention further relates to arrangements and combinations of parts which will be hereinafter described and more particularly pointed out in the appended claims.

A preferred form of my invention is shown in the drawings in which Fig. 1 is a sectional view of an underfeed Stoker and clinker grinder;

Fig. 2 is a plan view of m improved driving mechanism for the cli er grinder roll;

Fig. 3 is a side elevation of the parts shown in Fig. 2; and l Fig. 4, is a diagrammatic view of a sys` tem of electrica-l connections for the driving motor, other parts being shown in broken mes.

Referring to Fig. 1, I have shown a sectional view of parts of an underfeed stoker of a common form having a retort 10 to which fuel is fed from a hopper 11 by a feeding ram 12. The ash and refuse is discharged at the rear of the retort and moves downward over a rocking discharge plate 13 until it engages the clinker grinder roll 14. The side walls of the retort 10 are commonly reciprocated and the discharge plates 13 are pivotally connected thereto at their upper ends. The upper ends of the discharge plates thus receive a forward and rearward movement while the lower ends have a vertical feeding movement adjacent the grinder roll 14. Cams 15 provide a supporting -surface for rolls 16 mounted on the under side of the plates 13 and these cams may be adjusted about their axis to vary the space between the plates 13 and the roll 14. The parts thus far described may be of the usual construction and form no part of my present invention.

A sprocket wheel 20 (Fig. 3) is fixed to the end of the clinker grinder roll and is connected by a chain 21 to a sprocket wheel on a shaft 22 having a worm wheel 23 engaged by a worm 24 on a shaft 25 directly connected to the armature of a reversible electric motor 26. The shaft 22 is also connected by a driving chain 27 to a shaft 28 havmg a nut 29 threaded thereon but held from rotation therewith. At the opposite ends of its path .of travel, the nut 29 engages switches 30 and 31 in the control circuits of the motor 26. A suitable switch plate 32 is provided with push buttons 55, 56 and 57 for controlling the circuits for the motor 26.

The ldetails ofthe electrical circuits and connections form no part of my present invenBtionbut are indicated diagrammatically 1n 1g. f The push buttons 55 and 56 are provided for start-ing the motor ineither desired direction and the third push button 57 may be used to break the circuit and -stop the vmotor at any desired intermediate point.

The electrical connections as diagrammatically shown in Fig. 4 are as follows The motor 26 receives power through a power circuit comprising the wires 60, -61 and 62. The main wire 61 is connected through the-wire 63 to the normally open switch or button 56 and to the normall closed switch or button 57. This switch 5 is connected by a wire 64 to the normally open switch 55 and also to the contactposts 52 and 53. 1

Assuming` that the switch 30 is closed and that the switch 55 is also momentarily closed, a circuit is thenjcompleted throu h the wire 63, the switch 57, a portion of t e wire 64, the switch 55 and a wire 65, to a solenoid 66 which in turn is connected by a wire 67 to the main wire 62. The solenoid attracts a lever 68 which has a connection 68* through which it closes a series of switches 69, 70 and 71. The switch 69 controls a parallel connect-ion through the switch 30, wire 72, switch 69, and a portion of the wire to the solenoid66. This latter connection remains closed after the switch 55 is released and thus keeps the motor in operation. The switches 70 and 71 close the circuits through the main wires 61 and 62 and connections 61il and 62'* to the motor 26, the wire 60 being permanently connected thereto.

los

'v nut 29 reaches the end of its When the travelling nut 29 breaks the solenoid circuit by opening the switch 30, the lever 68 is released and is returned to normal open position by springs 73 and the motor is immediately stopped. If at any time the switch 57 is o ened, the same effect will be produced as 1s produced by o ning the switch 30, the solenoid circuit wil be broken, and the motor will be stopped.

The operation of the remaining parts of the control mechanism under the control of the switch 56 is identical, with the exception that the wires 61 and 62 will be reversely connected to the wires 62l and 61'* and that the .motor 26 will be rotated in the opposite direction.

The connections above described are illus- `trative only and in themselves form no part of my invention. Any other suitable and convenient controlling devices may be substituted for those herein shown.

It thus appears from the specific description that when one of the push buttons in the switch plate 32 is pressed, the motor 26 will be started in a given direction and will continue to rotate the grinder roll 14 until the ath of travel and enga es one of the switc es 30 or 31, opening t e same to break the circuit and sto the motor.

hen the clinker grinder is to be a ain operated, a second ush button in the p ate 32 is used to start t e motor in the opposite direction, whereupon it will continue to operate until the nut 29 engages the opposite switch 30 or 31 and again stops the motor. I have thus provided mechanism by which the clinker grinder roll 14 may be actuated to a predetermined extent in opposite directions alternately. The extent of the angular movement may be varied by changing the speed relation between the shaft 22 and the travellin nut 30 or by varying the extent of trave of the nut before it engages thc switches.

The advantages of my invention will be readily ap arent, as the o erator has only to push a utton to start t e grinder, after whlch he need give the device no further attention but may devote himself to other features of his work. After the roll has been rotated to the predetermined extent, it will remain at rest until again started by the operator. The extent of movement may be easily ad'usted to remove the desired amount of ash and refuse, without uncovering the roll to such an extent as to expose it to the heat of the furnace.

Having thus described my invention and the advanta es thereof, I do not wish to be limited to t e details herein disclosed, but what I claim is 1. In a furnace, a clinker grinder, means to give said clinker grinder successive operative movements of predetermined extent alternately in opposite directions, means for automaticall stopping the movement of the clinker grin er at the limit of movement in each dlrection and manually controlled means for starting the movement in the opposite direction.

2. In a furnace, a clinker grinder roll, an electric motor, driving connections between said motor and said roll, the direction of rotation of said roll and motor each being revel-sible, means for reversing said motor, and automatic means to stop said motor after a predetermined movement of said roll in eit 1er direction.

In testimony whereof I have hereunto afiixed my signature.

4DAVID K. BEACH. 

